The subject matter disclosed herein relates to a chemical detector and, more particularly, to a chemical detector including a chemical agent aerosol vaporizer.
Chemical agents often exist as liquids at room temperature. Dispersal of these agents often results in aerosols of oily droplets rather than vaporous clouds. Chemical detectors are typically dependent, however, on the presence of vapor for detection and thus may not function properly or effectively in the absence of vapor. In addition, the inlet systems for chemical detectors tend to operate in the laminar flow regime to prevent loss of vapors to the inlet walls due to an increase in carrier surface interactions through turbulence. Unfortunately, aerosols in a laminar flow regime that have only minimal interactions with wall surfaces may not experience any added effects from surface area increases of the droplets.
To address these issues, some chemical detectors use a fine wire screen in the sample path to capture aerosol droplets. The screen is heated to vaporize the captured droplets whereupon the resultant vapor can be directed toward a downstream detector device. Drawbacks to these systems include the fact that the screen needs to be of sufficiently fine mesh to ensure that a large fraction of particles impact on the heated wires, but the fine mesh is relatively easily fouled by atmospheric particulates, such as dust, when operations are undertaken outside of a laboratory environment.